Recently I was flying a job with freshly charged batteries in my Inspire 2. Took off at 100%, and climbed to about 250'. Flew about 400' away and both batteries still read 100%. A few seconds after that, a warning message pops up-"Voltage difference too large." I look and one battery is at 0%, the other reads 99%. I brought it down and landed as quickly as I could. Checking the battery information page, both sets of cells on each battery were still in the low 4.0 volts/cell, on every cell. Each cell was within .03 of every other cell. Both batteries indicated around 95% charge left. However, if I switched to the main flight screen, one battery still read 0%. If I pressed the button on the side of each battery, one gave four solid lights, the other one flashing light. So, I put in another set of batteries, same exact thing happened. A third set of batteries from a different purchase lot performed normally and we completed our flight with no anomalies. This same behavior occurred about a week earlier with a third set of batteries.
When home, I charged the problem paired sets, and they didn't charge very long (indicating they really did have a charge. I placed a problem set in the aircraft, and turned it on and fired up the motors (no props). The load on the batteries was light, and it took an hour to drain to 70%, but now both batteries acted perfectly normal, draining in lockstep with each other.
The next day we flew low and close to test both sets and they performed completely normally, running them down to around 50% charge level.
The fact that in one week this happened with three tried and true battery sets, made me suspect of software/firmware/hardware in the aircraft. Each set had about 40 charge cycles on them, and had never been anything other than normal before this.
As I was writing this, another piece of information popped in to my head. I each instance, the batteries probably were below 15 degrees Celsius, and in all three cases of failure, the initial load was immediate and full (in positioning mode), so there was a significant load on the batteries before they had a reasonable time to warm up.
Has anyone else experienced this? I am also curious if the second battery in the aircraft had dropped to 0% (even though cells showed high voltage), if the aircraft would have fallen out of the air?
When home, I charged the problem paired sets, and they didn't charge very long (indicating they really did have a charge. I placed a problem set in the aircraft, and turned it on and fired up the motors (no props). The load on the batteries was light, and it took an hour to drain to 70%, but now both batteries acted perfectly normal, draining in lockstep with each other.
The next day we flew low and close to test both sets and they performed completely normally, running them down to around 50% charge level.
The fact that in one week this happened with three tried and true battery sets, made me suspect of software/firmware/hardware in the aircraft. Each set had about 40 charge cycles on them, and had never been anything other than normal before this.
As I was writing this, another piece of information popped in to my head. I each instance, the batteries probably were below 15 degrees Celsius, and in all three cases of failure, the initial load was immediate and full (in positioning mode), so there was a significant load on the batteries before they had a reasonable time to warm up.
Has anyone else experienced this? I am also curious if the second battery in the aircraft had dropped to 0% (even though cells showed high voltage), if the aircraft would have fallen out of the air?
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